Electric heating unit



se tfls. 1'925. 1,553,423

J. C. WOODSQN ELECTRIC HEATING UNIT Filed July 6, 1923 INVENTOR WITNESSES:

. Uh CIA/094500 ATTORNEY Patented Sept. 15, 1925.

1,5sa42a UNITED STATES PATENT OFFICE.

JAMES C. WOOIDSON, 033 EAST PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 WESTING- HOUSE ELECTRIC 6t MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIA.

ELECTRIC HEATING UNIT.

Application filed July 6, 1923.

.Y '0 all whom it may concern:

Be it known that I, JAMns C. VVoonsoN, a citizen of the United States, and a resident of East Pittsburgh, in the county of Alla gheny and State of Pennsylvania, have in vented new and useful Improvement in Electric Heating Units, of which the following is a specification.

My invention relates to electric heating devices and particularly to electric heating units.

The object of my invention is to provide a relatively simple and compact removable electric heating unit, that shall be capable of being easily and quickly applied to any device to be heated.

In practicing my invention, I provide a plurality of elongated, relatively narrow, refractory members of electric-insulating material, each having a plurality of undercut grooves extending laterally thereof in one face.

A plurality of these supporting members are located in co-extensive and closely ad jacent, parallel relation, and a terminal member supporting-bar is provided at each end of the plurality of refractory bars. Bars of non-oxidizing metal are provided at each side of the assembled group of refractory bars to hold them in their proper operative positions relatively to each other. The ends of the metal bars overhang the group of refractory bars and are perforated to per-- mit of placing therethrough a suitable supporting bolt. A helically wound resistor member is located in the undercut grooves and has its ends connected to suitable ter minal members on the end bars of refractory material.

In the single sheet of drawings,

Figure 1 is a top plan view of an electric heating unit embodying my invention,

Fig. 2 is a View, in end elevation thereof, and

Fig. 3 is a view, in side elevation, of one of the refractory resistor-supporting bars.

A quickly removable heating unit 11 comprises a plurality of refractory bars 12 of a suitable electric-insulating material that are relatively narrow and elongated, and are severally provided with a plurality of spaced and undercut grooves 13 in one of the faces thereof. The end portions of each of the bars 12 are of less thickness than the Serial No. 649,808.

main portion thereof, for a purpose to be hereinafter described in detail.

End bars 14 of substantially the same area in lateral section and of substantially the same length are provided at each end of the assembled group of bars 12 and are severally provided with an intermediate depressed portion 15 and end depressed portions 16 and 17. Ridges 18, of substantially H-form, are located between the depressed portions 15 and 16, and 15 and 17, respectively.

A helically wound resistor member 19 ea:- tends through the spaced grooves 13, being held in the lower portion thereof by the overhanging portions or teeth 21, as illustrated more particularly in Fig. 3 of the drawing. It is, of course, understood that the grooves 13 in the respective bars are in alinement when the bars 12 are located in parallel and co-entensive positions, substan tially as illustrated in Fig. 1 of the drawing.

Terminal members are mounted on the respective end bars 1 1 and may comprise bolts 22 and a plurality of nuts 23 having screw threaded engagement therewith, suitable openings 2 1 being provided in the end bars 1 1 to permit of mounting the bolts therein. The resistor member 19 may extend from one of the terminal members, say at the lefthand end of the assembled unit, through one outer to the right-hand end of the unit, then back in the next adjacent groove to the left hand end, then back and forth until its other end is secured to the intermediate terminal 11181111361 located in the bar 1 1 at the right hand end of the assembled unit, as illustrated in Fig. 1. In this way, it is possible to employ two spaced heating elements and to employ therewith any suitable or desired method of control to permit of selectively varying the energization of the heating elements.

It may be noted that the upstanding walls or ridges 18 are of such shape as to assist i. effectively insulating the end portions of the heating element from each other as is more particularly shown in the left hand end of Fig. 1.

Means for holding the bars 12 and 14: in proper operative positions relatively to each other comprise an angle bar member 25 that is made of a suitable nonoxidizable material such as a nickel chromium alloy and of a flat bar 26. The angle tar has one of its flanges fitting in a shoulder portion of the bars 12 and let and the bar 26 is located at the other surface of the bars substantially as illustrated in Fig. 2 of the drawin A plurality of flat head machine bolts and co-operating nuts 28 are provided for each end of the bars 12 and let whereby a substan tially unitary and easily removable heating unit structure is obtained.

The angle bar mei'nbers 25 may c "ad a short dis ance beyond the assembled group of bars and have elongated openings 29 at each end to permit of securing the assen1- bled heating unit against a suitable supporting surface or against a surface that is to be heated thereby.

The metal side bars 25 and 26 may be removed when it is desired to apply the heating unit against a curved surface that will support the same. The helically wound resistor member serves to hold the refractory bars in substantially their operative positions while permitting them to adjust themselves to the contour of the surface against which they are located.

The device embodying my invention thus provides a relatively simple, easily assembled and disassembled heating unit structure comprising relatively few parts that shall permit of radiating a relatively large amount of the heat directly against any surface or body to be heated, and that shall embody means to permit of securing it by relatively simple means against a supporting surface or against the surface to be heated.

i arious modifications and changes may be made without departing from the spirit and scope of the invention, and l therefore, that only such limitations shall be placed thereon as are imposed by the prior art or are set forth in the appended claims.

I claim as my invention:

1. An electric heating unit con'iprising a plurality of relatively narrow, elongated, refractory bars located in adjacent relation and each having undercut and laterally-extcnding grooves in one face thereof, an extend ed heating element located in the undercut grooves and means estending along the ends of said bars and secured thereto for holding all of said bars in proper operative positions relatively to each other.

2. An electric heating unit comprising a plurality of elongated and relatively narrow bars of refractory electric insulating material located in closely adjacent relation, each bar having a pluralm of spaced nadercut, and laterallyextending grooves in one face thereof, the grooves in. the bars being in lateral alinemcnt with each other, at helicallywound resistor member located in said undercut grooves, a refractory terminal-supporting bar at each end of said plurality of bars, terminal members for said resistor member on said end bars, and refractory and substantially non-oxidizable metal members at the ends of said bars for holding them in proper operative positions relatively to each other.

3. An electric heating unit iomprising a plurality of laterally-grooved, narrow, elongated, refractory bars located in coertensive and closely adjacent relation, means secured to the ends of said bars for holding them in such positions, and an electric heat-- ing clement extending bacl; and forth in said grooves.

&. An electric heating unit comprising a plurality of laterally-grooved, narrow, elongated, refractory bars located in co-e1-:-- tensive and closely adjacent relation, an electric heating element located in said grooves, and means secured to the ends of said refractory bars for holding them. in their proper operative positions relatively to each other and for permitting the mounting of the heating unit in any desired operative position.

in testimony whereof, I have hereunto subscribed my name this 2nd day of July, 1923.

JAMES C. VUODEVON. 

